Mesogenic alkenyl functional maleimides and thermosets thereof

ABSTRACT

Compounds containing at least one alkenyl group, at least one maleimide group and at least one rodlike mesogenic moiety are prepared by reacting one or more aminophenols containing one or more rodlike mesogenic moieties with a stoichiometric quantity of a maleic anhydride per amine group of said aminophenol and then alkenylating the resulting phenolic functional maleimide.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a division of application Ser. No. 07/675,603 filedMar. 25, 1991 which is incorporated herein by reference in its entiretynow U.S. Pat. No. 5,159,030.

FIELD OF THE INVENTION

The present invention concerns alkenyl functional maleimides containingone or more rodlike mesogenic moieties.

BACKGROUND OF THE INVENTION

Copolymerization products of compounds containing two or more alkenylgroups with compounds containing two or more maleimide groups are knownfor example in U.S. Pat. No. 4,288,583; in U.S. Pat. No. 4,100,140; inU.S. Pat. No. 4,923,928 as well as from H. D. Stenzenberger, P. Konig,M. Herzog, W. Romer, M. S. Canning and S. Pierce, 18th InternationalSAMPE Technical Conference, 18, pages 500-509 (1986); H. Nakamura, M.Yamagiwa, K. Asagi, K. Kamio and S. Kanagawa, 18th International SAMPETechnical Conference, 18, pages 694-704 (1986); H. D. Stenzenberger, P.Konig, M. Herzog, W. Romer, S. Pierce, K. Fear and M. S. Canning, 19thInternational SAMPE Technical Conference, 19, pages 372-385 (1987); H.D. Stenzenberger, P. Konig, W. Romer, M. Herzog, S. Pierce and M.Canning, 32nd International SAMPE Symposium, 32, pages 44-58 (1987) andJ. King, M. Chaudhari and S. Zahir, 29th National SAMPE Symposium, 29,pages 392-408 (1984). Representative of said copolymerization productsare those prepared by copolymerization of o,o'-diallylbisphenol A oro,o'-dipropenylbisphenol A withN,N'-(methylene-di-phenylene)bismaleimide. Preparation of saidcopolymerization products always requires premixing or contactingtogether two separate components; the polyalkenyl compound and thepolymaleimide compound.

The novel compositions of the present invention simultaneously containboth an alkenyl group and a maleimide group as well as one more rodlikemesagenic moieties. Thus, said compositions avoid the premixing orcontacting together of separate polyalkenyl and polymaleimide componentsto provide products containing alkenyl group and maleimide groupcopolymerization structures. The presence of one or more rodlikemesogenic moieties provides structure capable of being oriented duringprocessing and/or curing of the alkenyl functional maleimides.

SUMMARY OF THE INVENTION

The present invention pertains to alkenyl functional maleimidecompositions containing one or more rodlike mesogenic moieties,particularly those represented by the following Formulas I, II, III orIV ##STR1## wherein at least about 80 percent of the --A-- linkages inFormulas I, II and IV and the direct bond in Formula III and the Ygroups are in the para position with respect to each other; one Y groupis an alkenyloxy group represented by the formulas --O--CR¹ ═CHR¹,--O--CHR¹ --CR¹ ═CHR¹, ##STR2## and the other Y group is a maleimidegroup represented by the formula ##STR3## each A is independently --CR¹═CR¹ --, --C.tbd.C--, --N═N--, --CR¹ ═N--, --O--CO--, --NR¹ --CO--,--CR¹ ═N--N═CR¹ --, --CR¹ ═CR¹ --CO--, --CO--O--, --CO--NR¹ --,--CO--CR¹ ═CR¹ --, --CR¹ ═CR¹ --O--CO--(CH₂)_(n') --, --N═CR¹ --,--(CH₂)_(n') --CO--O--CR¹ ═CR¹ --, --CR¹ ═CR¹ --O--CO--, --CO--O--CR¹═CR¹ --, --CO--O--N═CR¹ --, --CR¹ ═N--O--CO--, --CR¹ ═CR¹ --CO--O--,--CO--S--, --O--CO--CR¹ ═CR¹ --, --CR¹ ═CR¹ --CO--O--(CH₂)_(n') --,--S--CO--, --(CH₂)_(n') --O--CO--CR¹ ═CR¹ --, --CHR¹ --CHR¹ --CO--O--,--O--CO--CHR¹ --CHR¹ --, --C.tbd.C--C.tbd.C--, --CR¹ ═CR¹ --CR¹ ═CR¹ --,--CO--NR¹ --NR¹ --CO--, ##STR4## each A' is independently a divalenthydrocarbyl group having from 1 to about 10, preferably from 1 to about4, carbon atoms; each A" is independently an alkylene group having from1 to about 10 carbon atoms, preferably from 1 to about 4 carbon atoms, adirect bond, --O--, --CO--, --S--, --S--S--, --SO--, --SO₂ -- or--O--CO--O--; each A¹ is independently a --CO--, --O--CO--, --CO--O--,--CO--NR¹ --, or --NR¹ --CO-- group; each R is independently hydrogen ora hydrocarbyl or hydrocarbyloxy group having from 1 to about 10,preferably from 1 to about 4, carbon atoms, a halogen atom, preferablychlorine or bromine, a nitro group, a nitrile group, a phenyl group or a--CO--R¹ group; each R¹ is independently hydrogen or a hydrocarbyl grouphaving 1 to about 3 carbon atoms; n has a value of zero or one; n' hasan average value from zero to about 6, preferably zero to about 3; and phas an average value from 1 to about 30, preferably from 1 to about 3.The aromatic rings can also contain one or more heteroatoms selectedfrom N, O, S and the like.

Another aspect of the present invention pertains to compositionsresulting from curing (thermosetting) one or more of the alkenylfunctional maleimides containing one or more rodlike mesogenic moieties,optionally in the presence of one or more curing agents or curingcatalysts.

Another aspect of the present invention is directed to polymerizablecompositions comprising a mixture containing

(A) at least one thermosettable alkenyl functional maleimide containingone or more rodlike mesogenic moieties; and

(B) at least one of

(1) at least one polycyanate or polycyanamide;

(2) at least one epoxy resin;

(3) at least one polymaleimide;

(4) at least one polyamine;

(5) at least one polyphenol;

(6) at least one compound containing one or more polymerizableethylenically unsaturated group(s);

(7) at least one compound which contains in the same molecule both acyanate or cyanamide group and a polymerizable ethylenically unsaturatedgroup;

(8) at least one compound which contains in the same molecule both a1,2-epoxide group and a polymerizable ethylenically unsaturated group;

(9) at least one compound which contains in the same molecule both amaleimide group and a alkenyl group and does not contain rodlikemesogenic structures;

(10) at least one prepolymer of any of the aforesaid components (1)through (9) or any combination of any two or more of said components; or

(11) a mixture of any two or more of components (1) through (10) in anyproportion and any combination.

Another aspect of the present invention pertains to compositionsresulting from polymerizing the aforementioned polymerizablecompositions.

A further aspect of the present invention pertains to products resultingfrom orienting any of the aforementioned polymerizable compositions.

The term prepolymers as employed herein means that the compound has beenhomooligomerized or cooligomerized or interoligomerized orhomopolymerized or copolymerized or interpolymerized so as to cause anincrease in molecular weight, but not to such an extent that the producthas become cured, i.e. insoluble and infusible, but rather, the productis capable of being subsequently cured to an insoluble, infusible state.

DETAILED DESCRIPTION OF THE INVENTION Preparation of the AlkenylFunctional Maleimides Containing One or More Rodlike Mesogenic Moieties

The alkenyl functional maleimides of the present invention are preparedby reacting one or more aminophenols containing one or more rodlikemesogenic moieties with a stoichiometric quantity of a maleic anhydrideper amine group of said aminophenol in the presence of a suitablesolvent and then alkenylating the resulting phenolic functionalmaleimide.

Suitable aminophenols which can be employed herein to prepare thealkenyl functional maleimides containing one or more rodlike mesogenicmoieties include, for example, any compound which has an average of onearomatic hydroxyl group and aromatic primary amino group per moleculeand include, for example, those represented by the Formulas V, VI, VIIor VIII ##STR5## wherein at least about 80 percent of the --A-- linkagesin Formulas V, VI and VIII and the direct bond between the two aromaticrings in Formula VII and the Y¹ groups are in the para position withrespect to each other; one Y¹ group is --OH and the other is --NH₂ ;each A, A', A", A¹, R, R¹, n, n' and p are as hereinbefore defined. Thearomatic rings can also contain one or more heteroatoms selected from N,O, S and the like.

The term hydrocarbyl as employed herein means any aliphatic,cycloaliphatic, aromatic, aryl substituted aliphatic or cycloaliphatic,or aliphatic or cycloaliphatic substituted aromatic group. The aliphaticor cycloaliphatic groups can be saturated or unsaturated. When appliedto the A' group of Formulas III and VII, the hydrocarbyl group can alsocontain one or more heteroatoms selected from N, O, S and the like.Likewise, the term hydrocarbyloxy means a hydrocarbyl group having anoxygen linkage between it and the carbon atom to which it is attached.

Particularly suitable aminophenols are, for example, ##STR6## wherein n"has a value from 1 to about 10, ##STR7## mixtures thereof and the like.

Suitable maleic anhydrides include, for example, those represented bythe Formula IX ##STR8## wherein R¹ is as hereinbefore defined. Suitablemaleic anhydrides include maleic anhydride, methyl maleic anhydride,mixtures thereof and the like. Most preferred as the maleic anhydride ismaleic anhydride, per se.

Suitable solvents include aliphatic monocarboxylic acids such as aceticacid, propionic acid, mixtures thereof and the like. Most preferred asthe solvent is acetic acid. The maleimic acid resulting from reaction ofa maleic anhydride and an aminophenol compound, typically in an inertsolvent such as chloroform, toluene or dioxane, may be isolated thendehydrated in an aliphatic monocarboxylic acid to the correspondingphenolic functional maleimide. Alternately, the reaction may beperformed in a single continuous step in the aliphatic monocarboxylicacid solvent. The product resulting from this reaction is a phenolicfunctional maleimide represented by the Formulas X, XI, XII and XIII##STR9## wherein R, R¹, A, A', A", A¹, n, n' and p are as hereinbeforedefined.

Alkenyl functional maleimide compositions containing one or more rodlikemesogenic moieties are conveniently prepared by reacting astoichiometric quantity up to a stoichiometric excess of an alkenylhalide with a phenolic functional maleimide containing one or morerodlike mesogenic moieties, such as those represented by Formulas X, XI,XII and XIII, in the presence of a stoichiometric quantity of a basematerial. A stoichiometric excess of the alkenyl halide may beefficacious to provide not only the required alkenyl halide reactant butalso solvent for the reaction.

Suitable alkenyl halides include the alkenyl chlorides, bromides andiodides such as, for example, allyl chloride, allyl bromide, methallylchloride, methallyl bromide, vinylbenzyl chloride, vinylbenzyl bromide,isopopropenylbenzyl chloride, mixtures thereof, and the like. Allylchloride and vinylbenzyl chloride are most preferred as the alkenylhalides.

Suitable base compounds include both inorganic bases and tertiary aminessuch as sodium hydroxide, potassium hydroxide, potassium carbonate,trimethylamine, triethylamine, mixtures thereof, and the like. Sodiumhydroxide and potassium hydroxide are most preferred as the base.

Suitable solvents which may optionally be used for the alkenylationreaction include aliphatic ketones, chlorinated hydrocarbons, aliphaticand cycloaliphatic ethers and diethers, aromatic hydrocarbons,N-methylpyrrolidone, N,N-dimethylformamide, mixtures thereof and thelike. Dioxane, methylethylketone, methylene chloride or chloroform areparticularly suitable as the solvent. If desired one or more phasetransfer catalysts such as benzyltrialkylammonium salts ortetraalkylammonium salts may be used to facilitate the alkenylationreaction.

Reaction temperatures of from about 25° C. to about 150° C. areoperable, with reaction temperatures of 35° C. to 100° C. beingpreferred. Reaction times can vary substantially, for example, as afunction of the reactants being employed, the reaction temperature,solvent(s) used, the scale of the reaction, and the like, but aregenerally between 15 minutes and 24 hours, with reaction times of 2hours to 8 hours being preferred.

The propenyl functional maleimide compositions containing one or morerodlike mesogenic moieties may be conveniently prepared viaisomerization of the corresponding allyl functional malemidecompositions containing one or more rodlike mesogenic moieties. Methodsfor the isomerization of allyl groups, to propenyl groups are reportedby T. J. Prosser, Journal the American Chemical Society, 83, pages1701-1704 (1961) and by C. C. Price and W. H. Snyder, Journal of theAmerican Chemical Society, 83, page 1773 (1961).

Curing of the Alkenyl Functional Maleimides Containing One or MoreRodlike Mesognic Moieties

The alkenyl functional maleimides containing one or more mesognic orrodlike structure(s) are cured (thermoset) by heating from about 50° C.to about 450° C., preferably by heating from 100° C. to 350° C.,optionally in the presence of a suitable catalyst. Suitable catalystsinclude, for example, acids, bases, salts, free radical formingmaterials, nitrogen and phosphorous compounds, such as for example,Lewis acids such as AlCl₃, BF₃, FeCl₃ TiCl₄, ZnCl₂, SnCl₄ ; protonicacids such as HCl. H₂ SO₄, H₃ PO₄ ; aromatic hydroxy compounds such asphenol, p-nitrophenol, pyrocatechol, dihydroxynaphthalene; organicperoxides and hydroperoxides such as t-butylperoxybenzoate, benzoylperoxide, t-butylhydroperoxide; azo and diazo compounds such asazobisisobutyronitrile; sodium hydroxide, sodium methylate, sodiumphenolate, trimethylamine, triethylamine, tributylamine,N,N-tetramethyldiaminodiphenyl methane, 2-phenylmidazole,diazobicyclo-(2,2,2)-octane, quinoline, isoquinoline,tetrahydroisoquinoline, tetraethylammonium chloride, pyridine-N-oxide,tributyl phosphine, zinc octoate, tin octoate, zinc naphthenate, cobaltnaphthenate, cobalt octoate, cobalt acetylacetonate and the like. Alsosuitable as catalysts are the metal chelates such as, for example, thechelates of transition metals and bidentate or tridentate ligands,particularly the chelates of iron, cobalt, zinc, copper, manganese,zirconium, tintanium, vanadium, aluminum and magnesium. These and otheroperable catalysts are disclosed in U. S. Pat. Nos. 3,694,410 and4,094,852 which are incorporated herein by reference in their entirety.The quantity of catalyst used, if any, depends on the structure of theparticular catalyst, the structure of the alkenyl functional maleimidebeing cured, the cure temperature, the cure time, and the like.Generally, catalyst concentrations of from about 0.001 to about 5percent by weight are preferred.

B-staging or prepolymerization of the compositions of the alkenylfunctional maleimides of the present invention can be accomplished byusing lower temperatures and/or shorter curing times. Curing of the thusformed B-staged (prepolymerized) resin can then be accomplished at alater time or immediately following B-staging (prepolymerization) byincreasing the temperature and/or curing time.

The cured (thermoset) products prepared from the alkenyl functionalmaleimides containing rodlike mesogenic structure(s) can possess acomplex variety of curing structures. Included are the alkenyl grouphomopoylmerization structure(s) such as, for example, those described byN. G. Gaylord, Journal of Polymer Science, XIII, pages 71-78 (1956); C.E. Schildknecht, Allyl Compounds and Their Polymers (IncludingPolyolefins), Wiley-Interscience, New York (1973); A. Shimizu, T. Otsuand M. Imoto, Bulletin of the Chemical Society of Japan, 41, pages953-959 (1968); H. Raech, Jr., Allytic Resins and Monomers, ReinholdPublishing Corporation, New York (1965); Allyl Compounds in Kirk OthmerEncyclopedia Of Chemical Technology, third edition, volume 2, John Wileyand Sons, New York, pages 97-108 (1978); R. Alexander, A. Jefferson andP. D. Lester, Journal of Polymer Science: Polymer Chemistry Edition, 19,pages 695-706 (1981); and J. P. Kennedy, Cationic Polymerization,Wiley-Interscience, New York, pages 296-330 (1975). Certain of thealkenyloxy functional maleimides, for example, the allyloxy functionalmaleimides, can undergo catalytic and/or thermally induced Claisenrearrangement to the C-allyl isomer prior to polymerization.Furthermore, K. M. Hui and L. C. Yip, Chemical Communications, pages825-826 (1971) have demonstrated intramolecular rearrangement of anallyloxy aromatic compound during the propagation step of cationicpolymerization, thus similar rearrangement of the allyloxy functionalmalemides to the present invention may be expected to occur usingidentical or similar polymerization methods. Phenolic hydroxyl groupsformed during the rearrangement reaction may form addition structurederived from copolymerization of the phenolic hydroxyl group and themalemide unsaturation.

Additionally included is the maleimide group homopolymerizationstructure ##STR10## and various alkenyl group and maleimide groupcopolymerization structures. A typical example are the allyl group andmalemide group copolymerization structures: ##STR11##

A second example of copolymerization structures are those derived frompropenyl group and maleimide group copolymerization: ##STR12##

Other functionalities that are present in the alkenyl functionalmaleimides that participate in the curing process can change the curingstructures present.

Polycyanates or Polycyanamides which can be Employed in the Curable andCured Compositions

Suitable polycyanates or polycyanamides which can be employed to preparethe polymerizable mixtures of the present invention include, forexample, those represented by the following Formulas XIV, XV, XVI, XVII,XVIII, XIX and XX. ##STR13## wherein A, A', A", p and n are ashereinbefore defined; each Y² is a --O--C.tbd.N or a --N--R¹ --C.tbd.Ngroup; each A² is independently an alkylene group having from 1 to about10, preferably from 1 to about 4 carbon atoms or a ##STR14## each R' isindependently hydrogen, a hydrocarbyl or hydrocarbyloxy group havingfrom 1 to about 10, preferably 1 to about 4 carbon atoms, a halogen,preferably chlorine or bromine, a phenyl group, a --O--C.tbd.N group, ora --N--R¹ --C.tbd.N group; each R" is independently hydrogen, ahydrocarbyl or hydrocarbyloxy group having from 1 to about 10,preferably 1 to 4 carbon atoms, a halogen, preferably chlorine orbromine, or a phenyl group; p' has a value from zero to about 100,preferably from zero to about 30; p" has a value of from zero to about10, preferably from zero to 3 and m has a value of from about 0.001 toabout 6, preferably from about 0.01 to about 3. The aromatic rings canalso contain one or more heteroatoms selected from N, O, S, and thelike.

Suitable polycyanantes or polycyanamides represented by Formulas XIV,XV, XVI, XVII, XVIII, XIX and XX include, for example, bisphenol Adicyanate, the dicyanates of 4,4'-dihydorxydiphenyl,4,4'-dihydroxydiphenyl oxide, resorcinol, hydroquinone,4,4'-thiodiphenol, 4,4'-sulfonyldiphenol, 4,4'-dihydroxystilbene,4,4'-dihydroxy-alpha-methylstilbene, 4,4'-dihydroxybenzanilide,2,2'-dihydroxystilbene, 4,4'-dihydroxydiphenylazomethine,4,4'-dihydroxy-alpha-chlorostilbene, 3,3',5,5'-tetrabromobisphenol A,2,2',6,6'-tetrabromobisphenol A, 2,2'-dihydroxydiphenyl,3,3'-dimethoxybisphenol A, 4,4'-dihydroxydiphenylcarbonate,dicyclopentadiene diphenol, 4,4'-dihydroxybenzophenone,4,4'-dihydroxydiphenyl methane, tricyclopentadiene diphenol, thetricyanate of tris(hydroxyphenyl)methane, the tetracyanate of2,2',4,4'-tetrahydroxydiphenyl methane, the polycyanate of aphenolformaldehyde condensation product (novolac), the polycyanate of adicyclopentadiene and phenol condensation product, the dicyanamide of4,4'-diaminodiphenyl methane, the cyanate cyanamide of p-aminophenol,and the like.

The polycyanates or polycyanamides are prepared by reacting thecorresponding polyphenol, polyamine or aminophenol precursor with acyanogen halide in the presence of a base material.

Epoxy Resins which can be Employed in the Curable and Cured Compositions

Suitable epoxy resins which can be employed to prepare the polymerizablemixtures of the present invention include materials having an average ofmore than one vicinal epoxide group per molecule, such as, for example,the epoxy resins represented by the following Formulas XXI, XXII, XXIII,XXIV, XXV, XXVI, XXVII, XXVIII, XXIX, XXX ##STR15## wherein A, A², A',A", R, R¹, R", m and n are as hereinbefore defined; each R² isindependently hydrogen, or a hydrocarbyl or halohydrocarbyl group havingfrom 1 to about 6, preferably 1 to about 2 carbon atoms; Q is a directbond, --CH₂ --S--CH₂ --, --(CH₂)_(n") --, or ##STR16## m' has a value offrom zero to about 30, preferably from about zero to about 5; m" has avalue from 1 to about 10, preferably from about 1 to about 4 and n" hasan average value from about 1 to about 10. The aromatic rings can alsocontain one or more heteroatoms selected from N, O, S and the like.

Particularly suitable epoxy resins represented by Formulas XXI, XXII,XXIII, XXIV, XXV, XXVI, XXVII, XXVIII, XXIX, and XXX are the diglycidylethers of resorcinol, hydroquinone, dihydroxydiphenyl methane, bisphenolA, 3,3',5,5'-tetrabromobisphenol A, 4,4'-sulfonyldiphenol,4,4'-thiodiphenol, 4,4'-dihydroxydiphenyl oxide,4,4'-dihydroxybenzophenone, 2,2'-dihydroxydiphenyl, dicyclopentadienediphenol, tricyclopentadiene diphenol, 4,4'-dihydroxydiphenyl,4,4'-dihydroxystilbene, 4,4'-dihydroxy-alpha-methylstilbene,4,4'-dihydroxy-alpha-cyanostilbene, 4,4'-dihydroxychalcone,4,4'-dihydroxydiphenylacetylene, 4,4'-dihydroxydiphenylazomethine,4,4'-dihydroxyazobenzene, 4,4'-bis(4-hydroxyphenoxy)diphenyl,4,4'-dihydroxybenzanilide, ethylene glycol, thiodiglycol, diethyleneglycol, dipropylene glycol, polypropylene glycol, polyethylene glycol,1,4-cyclohexanediol, dibutylene glycol, the advancement reaction productof the diglycidyl ether of bisphenol A and bisphenol A, the advancementreaction product of the diglycidyl ether of4,4'-dihydroxy-alpha-methylstilbene and4,4'-dihydroxy-alpha-methylstilbene, the triepoxide of p-aminophenol,the tetraepoxide of 4,4'-diaminodiphenyl methane, the triglycidyl etherof tris(hydroxyphenyl)methane, the tetraglycidyl ether of2,2',4,4'-tetrahydroxydiphenyl methane, the polyglycidyl ether of aphenolformaldehyde condensation product (novolac), the polyglycidylether of a dicyclopentadiene or oligomer thereof and phenol or halogenor alkyl substituted phenol condensation product and the like.

The aforementioned epoxy resins can be prepared by reaction of apolyphenol (polyamine, aminophenol, polyalkylene glycol) with anepihalohydrin and a basic acting material. Said reaction generallyinvolves two distinct steps: coupling reaction of the epihalohydrin andpolyphenol to provide a halohydrin intermediate and dehydrohalogenationreaction of the halohydrin intermediate to provide the glycidyl etherproduct. Suitable catalysts and reaction conditions for preparing epoxyresins are described in the Handbook of Epoxy Resins by Lee and Neville,McGraw-Hill (1967) which is incorporated herein by reference.

Polymaleimides For Use In The Curable And Cured Compositions

Suitable polymaleimides which can be employed to prepare thepolymerizable mixtures of the present invention include, for example,those represented by the Formulas XXXI, XXXII, XXXIII, XXXIV, XXXV,XXXVI, XXXVII and XXXVIII ##STR17## wherein A, A², A', A", R, R¹, R", m,n and p are as hereinbefore defined and Q¹ is a divalent hydrocarbylgroup having from 2 to about 12 carbon atoms and may be linear orbranched aliphatic, cycloaliphatic or polycycloaliphatic. The aromaticrings can also contain one or more heteroatoms selected from N, O, S andthe like.

Particularly suitable polymaleimides represented by Formulas XXXI,XXXII, XXXIII, XXXIV, XXXV, XXXVI, XXXVII, and XXXVIII areN,N'-ethylenebismaleimide, N,N'-ethylenebis(2-methylmaleimide),N,N'-hexamethyl-enebismaleimide, N,N'-(oxydi-p-phenylene)bismaleimide,N,N'-(methylenedi-p-phenylene)maleimide,N,N'-(methyl-enedi-p-phenylene)bis (2-methylmaleimide),N,N'-(thio-di-p-phenylene)bismaleimde,N,N'-(sulfonyldi-m-phenylene)bismaleimide,N,N'-(isopropylidenedi-p-phenylene)bismaleimide, polymethylenepolyphenylene polymaleimides, the bismaleimide of 4,4'-diaminostilbene,the bismaleimide of 4,4'-diaminobenzanilide and the like.

The polymaleimides can be prepared by reacting a stoichiometric quantityof a maleic anhydride per amine group with a polyamine in the presenceof a suitable solvent, such as, for example, aromatic hydrocarbons,chlorinated hydrocarbons or N,N-dimethylformamide. The polymaleamic acidresulting from reaction of a maleic anhydride and a polyamine may beisolated and dehydrated to the desired polymaleimide. Alternately, thereaction may be performed in a single continuous step. Detailedprocedures for preparing polymaleimides can be found in U.S. Pat. Nos.2,444,536; 2,462,835; and Journal of Polymer Science: Part A: PolymerChemistry, Vol. 27, pages, 375-388 (1989) which are incorporated hereinby reference.

Polyamines Suitable for Use in the Curable and Cured Compositions

Suitable polyamines which can be employed to prepare the polymerizablemixtures of the present invention, include those containing one or moreof the rodlike mesogenic structure(s) already described herein, as wellas any of the other known polyamines which do not contain rodlikemesogenic structures. Typical representatives of said polyamines free ofrodlike mesogenic structures include 1,4-diaminobutane,1,6-hexanediamine, 1,12-diaminododecane,2-methyl-4-ethyl-1,8-diaminooctane, 1,4-diaminocyclohexane,4,4'-diaminodiphenyl methane, 1,4-diaminobenzene,tris(aminophenyl)methane, anilineformaldehyde condensation products andthe like.

Polyphenols Suitable For Use In The Curable And Cured Compositions

Suitable polyphenols which can be employed to prepare the polymerizablemixtures of the present invention, include those containing one or moreof the rodlike mesogenic structure(s) already described herein as wellas any of the other known polyphenols which do not contain rodlikemesogenic structures. Typical representatives of said polyphenols freeof rodlike mesogenic structures include resorcinol,4,4'-sulfonyldiphenol, 4,4'-dihydroxydiphenyl oxide,tris(hydroxyphenyl)methane, phenolformaldehyde condensation products andthe like.

Polymerizable Unsaturated Monomers Suitable for Use in the Curable andCured Compositions

Suitable compounds containing one or more polmerizable ethylenicallyunsaturated group(s) which can be employed to prepare the polymerizablemixtures of the present invention include both those containing one ormore rodlike mesogenic structure(s) and those free of said structures.

Suitable polymerizable ethylenically unsaturated monomers containing oneor more rodlike mesogenic moieties are cataloged by Alexandre Blumstienin Liquid Crystalline Order in Polymers, published by Academic Press,New York, (1978) on pages 105-140; Mesomorphic Order in Polymers andPolymerization in Liquid Crystalline Media published by AmericanChemical Society (ASC Symposium Series 74), Washington, D.C. (1978) onpages 56-70; and N. A. Plate and V. P. Shibaev in Comb-Shaped Polymersand Liquid Crystals published by Plenum Press, New York (1987) on pages1-415; V. Percec, et.al., Polymer Bulletin, 17, pages 347-352 (1987); R.Duran and P. Gramain, Makromol. Chem., 188, pages 2001-2009 (1987); A.M. Mousa, et. al., Polymer Bulletin, 6, pages 485-492 (1982); H.Finklemann, et. al., Makromol. Chem., 179 pages 829-832 (1978); M.Portugall, et. al., Makromol. Chem., 183, pages 2311-2321 (1982) andU.S. Pat. Nos. 4,637,896 and 4,614,619, all of which are incorporatedherein by reference. Suitable polymerizable ethylenically unsaturatedmonomers containing one or more rodlike mesogenic moieties per moleculeare represented by the Formulas XXXIX or XXXX:

    M--Q.sup.2                                                 FORMULA XXXIX

    M--(Q.sup.3).sub.n --R.sup.3 --Q.sup.2                     FORMULA XXXX

wherein n and R¹ are as hereinbefore defined, M is a group containingtwo or more aromatic rings bridged by a rigid central linkage, R³ is adivalent hydrocarbon group having from one to about 12 carbon atoms andmay be linear, branched, cyclic, aromatic or a combination thereof andmay be substituted with one or more inert groups, such as, for example,a methoxy group, or may contain one or more inert heteroatom containinglinkages, such as, for example, an ether linkage; Q³ is --O--, --NR¹ --,--S--, --O--CO--, --CO--O--, --NR¹ --CO--, --CO--NR¹ --, --CO--,--O--CO--O--, --S--CO--, --CO--S--, --NR¹ --CO--O--, --O--CO--NR¹ --,--NR¹ --CO--NR¹ --; and Q² is a polymerizable ethylenically unsaturatedgroup. As a class, these monomers generally contain a --CH═CH₂, allyl,methallyl, propenyl, isopropenyl, acrylate or methacrylate group as thepolymerizable ethylenically unsaturated group and a linear divalentaliphatic, aliphatic ether, aliphatic polyether, aliphatic thioether orcycloaliphatic flexible spacer connecting the polymerizableethylenically unsaturated group and the rodlike mesogenic group(s)through a heteroatom linkage. Typical rodlike mesogenic groups includethose wherein two or more aromatic rings are bridged by a rigid centrallinkage wherein said rigid central linkage is required to bridge thearomatic rings to provide at least about 80 percent para substitution.The aromatic rings can be inertly substituted, however, unsubstitutedaromatic rings which maximize the molecular aspect ratio are preferred.Also preferred is a single inert substituent in the para position on thering not connected to the polymerizable ethylenically unsaturated group(either directly or via a flexible spacer). This type of substituent canbe used to enhance the molecular aspect ratio. Typical of these inertsubstituents are CH₃ O--, Cl--, NO₂ --, --C.tbd.N and the like. Thearomatic rings can also contain one or more heteroatoms selected from N,O, S and the like. Typical rigid central linkage groups for bridging thearomatic rings include, for example, a direct bond, --CR¹ ═CR¹ --,--C.tbd.C--, --N═N--, --CR¹ ═N--, --CR¹ ═N--N═CR¹ --, --CR¹ ═CR¹ --CO--,--O--CO--, --NR¹ --CO--, --CO--O--, --CO--NR¹ --, --CO--CR¹ ═CR¹ --,--CR¹ ═CR¹ --O--CO--(CH₂)_(n') --, --N═CR¹ --, --(CH₂)_(n') --CO--O--CR¹═CR¹ --, --CR¹ ═CR¹ --O--CO--, --CO--O--CR¹ ═ CR¹ --, --CO--O--N═CR¹ --,--CR¹ ═N--O--CO--, --CR¹ ═CR¹ --CO--O--, --CO--S--, --O--CO--CR¹ ═CR¹--, --CR¹ ═CR¹ --CO--O--(CH₂)_(n') --, --S--CO--, --(CH₂)_(n')--O--CO--CR¹ ═CR¹ --, --CHR¹ --CHR¹ --CO--O--, --O--CO--CHR¹ --CHR¹ --,--C.tbd.C--C.tbd.C--, --CR¹ ═CR¹ --CR¹ ═CR¹ --, --CO--NR¹ --NR¹ --CO--,##STR18## and the like; wherein R¹, A¹, n and n' are as hereinbeforedefined. As is well known in the prior art, all or a part of thearomatic rings can be replaced with other promesogenic structures, suchas, for example, the trans-cyclohexane ring or a cholesterol group.Additionally, it is has been demonstrated in the prior art thatefficacious rodlike mesogenic containing polymerizable ethylenicallyunsaturated monomers can be prepared with omission of the flexiblespacer between the polymerizable ethylenically unsaturated group and therodlike mesogenic group(s).

Generally, the ethylenically unsaturated monomers containing --CH═CH₂,acrylate, allyl, methallyl, propenyl, isopropenyl or methacrylate as thepolymerizable vinyl group and a linear divalent hydrocarbon groupconnecting the vinyl group and the rodlike mesogenic group throughheteroatom containing functional groups between the hydrocarbon spacerand the mesogenic group are most preferred. Thus, a mesogenic groupether linked to a --CH₂ --CH₂ --which is in turn linked to provide amethacrylate ester, that is, ##STR19## or a mesogenic group linked to avinyl group, that is, ##STR20## are examples of those species preferredas the ethylenically unsaturated monomer containing one or more rodlikemesogenic moieties.

Particularly suitable ethylenically unsaturated monomers containing arodlike mesogenic moiety include, for example, ##STR21## any combinationthereof and the like.

Suitable polymerizable ethylenically unsaturated monomers which do notcontain rodlike mesogenic structures can be selected from the many knownclasses of polymerizable vinyl monomers. Suitable such monomers include,for example, the vinyl aromatic compounds represented by the followingFormula XXXXI ##STR22## wherein each R¹ is as hereinbefore defined, Y³is independently hydrogen, a hydrocarbyl or hydrocarbyloxy group havingfrom 1 to about 5 carbon atoms, a vinyl group, an allyl group, amethallyl group, a propenyl group, a isopropenyl group, a nitro group, anitrile group, a halogen, such as chlorine or bromine or fluorine, or a--CO--R¹ group; each Y⁴ is independently hydrogen, a hydrocarbyl orhydrocarbyloxy group having from 1 to about 5 carbon atoms, or ahalogen, such as chlorine or bromine or fluorine and X is ##STR23## orthe acrylate or methacrylate compounds represented by the followingFormula XXXXII ##STR24## wherein R⁴ is a hydrocarbyl group having from 2to about 25 carbon atoms and may be branched, cyclic, polycyclic,saturated or unsaturated and R⁵ is hydrogen or a methyl group.

Typical polymerizable unsaturated monomers represented by Formula XXXXIinclude, for example, styrene, alpha-methylstyrene, o-, m-,p-chlorostyrene; o-, m-, p-bromostyrene; o-, m-, p-butylstyrene; o-, m-,p-methylstyrene; o-, m-, p-methoxystyrene; divinylbenzenes,trivinylbenzenes, o-, m-, p-isopropenylstyrene; o-, m-, p-allylstyrene;o-, m-, p-methallylstyrene; allylbenzene, methallybenzene,diallylbenzenes and the like.

Typical acrylate (methacrylate) esters represented by Formula XXXXIIinclude, for example, ethyl acrylate, n-butyl acrylate, n-butylmethacrylate, sec-butyl acrylate, 2-ethylhexyl acrylate, 2-ethylhexylmethacrylate, n-dodecyl acrylate, cyclohexyl acrylate, methylcyclohexylacrylate, norbornyl acrylate, dicyclopentadiene acrylate,methyldicyclopentadiene acrylate and the like.

Other suitable monomers include the acidic monomers, such as acrylic andmethacrylic acid; the amide monomers, such as acrylamide andN-methylacrylamide; the allyl monomers, such as diallylphthalate,triallylisocyanurate, diallylmaleate and dimethallylfumarate; the vinylhalides, such as vinyl chloride and vinyl bromide; the vinyl esters,such as vinyl acetate; the vinyl di and polycyclic aromatics, such asvinyl naphthalene; the vinyl nitriles, such as acrylonitrile; and thehydroxyalkyl acrylates and methacrylates, such as 2-hydroxyethylacrylate.

Compounds Containing Both a Cyanate or Cyanamide Group and aPolymerizable Ethylenically Unsaturated Group for Use in the Curable andCured Compositions

Suitable compounds which contain both a cyanate or cyanamide group and apolymerizable ethylenically unsaturated group in the same molecule thatcan be used to prepare the polymerizable mixtures of the presentinvention include, for example, those represented by the followingFormula XXXXIII ##STR25## wherein each Y² and R¹ are as hereinbeforedefined, Y⁵ is independently hydrogen, a hydrocarbyl or hydrocarbyloxygroup having from 1 to about 12 carbon atoms, a nitro group, a nitrilegroup, a halogen, such as chlorine or bromine or fluorine, or a --CO--R¹group; or a compound represented by the following Formula XXXXIV##STR26## wherein each Y², Y⁵ and R¹ are as hereinbefore defined.

Suitable compounds which contain a cyanate or cyanamide group and apolymerizable ethylenically unsaturated group in the same moleculerepresented by Formulas XXXXIII and XXXXIV include, for example, o-, m-,p-isopropenylphenyl cyanate; o-, m-, p-vinylphenyl cyanate;methyl-p-isopropenylphenyl cyanates; 3-chloro-4-isopropenylphenylcyanate; o-, m-, p-propenylphenyl cyanate; o-, m-, p-allylphenylcyanate; o-, m-, p-methallylphenyl cyanate and the like. Some of thealkenylphenol precursors to the alkenylphenyl cyanates represented byFormula XXXXIII, notably the vinylphenols, have a tendency to dimerizeor oligomerize thus leading to poly(alkenylphenyl)cyanates. It is mostpreferred that the alkenylphenyl cyanate be substantially free ofdimeric and/or oligomeric components, although it is operable to use analkenylphenyl cyanate containing substantial (up to 90 percent byweight) dimeric and/or oligomeric components. A specific preparation ofp-isopropenylphenyl cyanate is taught in Example 1 of U.S. Pat. No.4,559,399 which is incorporated herein by reference.

Compounds Containing Both a 1,2-Epoxide Group and a PolymerizableEthylenically Unsaturated Group for Use in the Curable and CuredCompositions

Suitable compounds which contain both a 1,2-epoxide group and apolymerizable ethylenically unsaturated group in the same molecule thatcan be used to prepare the polymerizable mixtures of the presentinvention include, for example, those represented by the followingFormulas XXXXV or XXXXVI ##STR27## wherein each Y⁵ and R¹ are ashereinbefore defined.

Suitable compounds which contain a 1,2-epoxide group and a polymerizableethylenically unsaturated group in the same molecule represented byFormulas XXXXV and XXXXVI include, for example, o-, m-,p-isopropenylphenyl glycidyl ether; o-, m-, p-vinylphenyl glycidylether; methyl-p-isopropenylphenyl glycidyl ethers;3-chloro-4-isopropenylphenyl glycidyl ether; o-, m-, p-propenylphenylglycidyl ether; o-, m-, p-allylphenyl glycidyl ether; o-, m-,p-methallyphenyl glycidyl ether and the like. Some of the alkenylphenolprecursors to the alkenylphenyl glycidyl ethers represented by FormulaXXXXV, notably the vinylphenols, have a tendency to dimerize oroligomerize thus leading to poly(alkenylphenyl)glycidyl ethers. It ismost preferred that the alkenylphenyl glycidyl ether be substantiallyfree of dimeric and/or oligomeric components, although it is operable touse an alkenylphenyl glycidyl ether containing substantial (up to 90percent by weight) dimeric and/or oligomeric components. The compoundswhich contain a 1,2-epoxide group and a polymerizable ethylenicallyunsaturated group in the same molecule are prepared using thecorresponding phenol containing a polymerizable ethylenicallyunsaturated group and the hereinbefore described chemistry used in thepreparation of epoxy resins.

Compounds Containing Both a Maleimide Group and a Alkenyl Group and noRodlike Mesogenic Structures Suitable for Use in the Curable and CuredCompositions

Suitable compounds which contain both a maleimide group and a alkenylgroup in the same molecule and do not contain rodlike mesogenicstructures that can be used to prepare the polymerizable mixtures of thepresent invention include, for example, those represented by thefollowing Formulas XXXXVII or XXXXVIII ##STR28## wherein each Y⁵, R¹, A"and n are as hereinbefore defined and Y is an alkenyloxy grouprepresented by the formulas; --O--CR¹ ═CHR¹, --O--CHR¹ --CR¹ ═CHR¹,##STR29##

Suitable compounds which contain a maleimide group and a alkenyl groupin the same molecule and do not contain rodlike mesogenic structuresrepresented by Formulas XXXXVII and XXXXVIII include, for example,##STR30## and the like. Alkenyl functional maleimide compositions whichdo not contain rodlike mesogenic structures are prepared by reacting thecorresponding phenolic functional maleimide, such as is taught in U.S.Pat. No. 4,683,276 and which is incorporated herein by reference, withan alkenyl halide in the presence of a base material.

METHOD FOR FORMING THE MIXTURES OF THE PRESENT INVENTION

The mixtures of the present invention can be prepared by directlycombining one or more of the desired component(s) with one or morealkenyl functional maleimides containing one or more rodlike mesogenicstructures or by addition of one or more of the desired components toone or more of the alkenyl functional maleimides containing one or morerodlike mesogenic structures in increments or stages. When a singlecomponent is to be added to one or more of the alkenyl, functionalmaleimides containing one or more rodlike mesogenic structures, saidcomponent may be prepolymerized (B-staged) or fully homopolymerized,prior to the addition. When two or more components are to be added toone or more of the alkenyl functional maleimides containing one or morerodlike mesogenic structures, said components may be partially ortotally copolymerized or reacted together, prior to the addition.Additionally, when two or more components are to be added to one or moreof the alkenyl functional maleimides containing one or more rodlikemesogenic structures, one component may be prepolymerized or fullyhomopolymerized in the presence of the other components, prior to theaddition. It is understood that one or more catalysts or acceleratorsamy be included where desired to facilitate the aforementionedcopolymerization, prepolymerization, homopolymerization or reaction ofone or more specific components.

The mixtures can comprise any amount of the compound or compoundscontaining at least one alkenyl group, at least one maleimide group andat least one rodlike mesogenic moiety and the other component orcomponents; however, the mixtures suitably contain from about 1 to about99, more suitably from about 99 to about 40, most suitably from about 95to about 70, percent by weight of the compound or compounds containingat least one alkenyl group, at least one maleimide group and at leastone rodlike mesogenic moiety and suitably from about 99 to about 1, moresuitably from about 60 to about 1, most suitably from about 30 to 5,percent by weight of the other component or components.

Polymerization (Curing) of the Polymerizable Mixtures

The mixtures of the present invention may be polymerized by heating fromabout 50° C. to about 450° C., preferably by heating from 100° C. to350° C., optionally in the presence of one or more suitable catalysts.For the mixtures containing of one or more of the alkenyl functionalmaleimides containing one or more rodlike mesogenic structures, wheneverone or more polymaleimides, compounds containing one or morepolymerizable ethylenically unsaturated group(s), compounds whichsimultaneously contain both a cyanate group or cyanamide group and apolymerizable ethylenically unsaturated group, compounds whichsimultaneously contains both a 1,2-epoxide group and a polymerizableethylenically unsaturated group or compounds which simultaneouslycontain both a maleimide group and a alkenyl group and no rodlikemesogenic structures are present, it is often desirable to utilize oneor more free radical forming catalysts for the purpose of polymerizingall or a part of said unsaturated groups. said free radical formingcatalysts include the organic peroxides and hydroperoxides as well asthe azo and diazo compounds. Preferred free radical forming catalystsinclude benzoylperoxide, t-butylhydroperoxide, t-butylperoxybenzoate,azobisisobutyronitrile, dicumylperoxide, di-tertbutylperoxide and cumenehydroperoxide. The quantity of catalyst used, if any, depends on thestructure of the particular catalyst, the structure of the componentsused in the polymerizable mixture, the cure structure desired, the curetime, the cure temperature, and the like. Generally, catalystconcentrations of from about 0.001 to about 2 percent by weight arepreferred. B-staging or prepolymerization of the mixtures of the presentinvention can be accomplished by using lower temperatures and/or shortercuring times. Curing of the thus formed B-staged (prepolymerized)mixture can then be accomplished at a later time or immediatelyfollowing B-staging (prepolymerization) by increasing the temperatureand/or curing time.

The polymerized (cured) mixtures possess a variety of curing structureswhich depend, in part, upon the amounts and types of individualcomponents used to prepare said mixture, the sequence of componentaddition and procedure used to prepare said mixture, the amounts andtypes of catalysts, if any, employed, the reaction times andtemperatures, and the like.

Mixtures of (A), one or more alkenyl functional maleimides containingone or more rodlike mesogenic structures and no other moieties reactivewith the alkenyl or maleimide group, and (B-3), one or morepolymaleimides and/or prepolymers of any of the aforementioned types ofcompounds, polymerize to produce the aforementioned curing structuresdelineated for the (A), alkenyl functional, maleimides containing one ormore rodlike mesogenic structures. It should be noted, however, that therelative mole ratio of alkenyl groups to maleimide groups can influencethe amounts of the various cure structures in the cured product. Forexample, a large excess of maleimide groups, provided by using a (B-3)polymaleimide in the copolymerizable compositions increases the amountof cure structure derived from reaction of two equivalents of maleimidegroups per equivalent of alkenyl group, as well as maleimide grouphomopolymerization structure, in the cured product.

Mixtures of (A), one or more alkenyl functional maleimides containingone or more rodlike mesogenic structures and no other moieties reactivewith the alkenyl, or maleimide group, and (B-2), one or more epoxyresins, polymerize to produce a complex structure, which can includethat derived from addition reaction of the maleimide group and theglycidyl ether group ##STR31## Additionally, curing structures derivedfrom homopolymerization of the maleimide groups, homopolymerization ofthe alkenyl groups, as well as copolymerization of the alkenyl andmaleimide groups can be present.

Mixtures of (A), one or more alkenyl functional maleimides containingone or more rodlike mesogenic structures and no other moieties reactivewith the alkenyl or maleimide group, and (B-4), one or more polyamines,polymerize to produce a complex structure including the additionstructure derived from the copolymerization reaction of the amine groupand the maleimide unsaturation. Additionally, curing structures derivedfrom homopolymerization of the maleimide groups, homopolymerization ofthe alkenyl groups, as well as copolymerization of the alkenyl andmaleimide groups can be present.

Mixtures of (A), one or more alkenyl functional maleimides containingone or more rodlike mesogenic structures and no other moieties reactivewith the alkenyl or maleimide group, and (B-5), one or more polyphenols,polymerize to produce a complex structure including the additionstructure derived from the copolymerization reaction of the phenolichydroxyl group and the maleimide unsaturation. Additionally, curingstructures derived from homopolymerization of the maleimide groups,homopolymerization of the alkenyl groups, as well as copolymerization ofthe alkenyl and maleimide groups can be present.

Mixtures of (A), one or more alkenyl functional maleimides containingone or more rodlike mesogenic structures and no other moieties reactivewith the alkenyl or maleimide group, and (B-6), one or morepolymerizable ethylenically unsaturated compounds, can polymerize toproduce a complex curing structure including structure derived from thecopolymerization reaction of the maleimide group and the polymerizableethylenically unsaturated groups(s), as well as structure derived fromthe copolymerization reaction of the alkenyl group and the polymerizableethylenically unsaturated group(s). Additionally, curing structuresderived from homopolymerization of the polymerizable ethylenicallyunsaturated groups, from homopolymerization of the maleimide groups,from homopolymerization of the alkenyl groups, as well ascopolymerization of the alkenyl and maleimide groups can be present.

Mixtures of (A), one or more alkenyl functional maleimides containingone or more mesogenic rodlike structures and no other moieties reactivewith the alkenyl or maleimide group, and (B-7), one or more compoundswhich simultaneously contain both a cyanate group and a polymerizableethylenically unsaturated group, or (B-8), one or more compounds whichsimultaneously contain both a 1,2-epoxide group and a polymerizableethylenically unsaturated group, or (B-9), one or more compounds whichsimultaneously contain both a maleimide group and an alkenyl group anddoes not contain rodlike mesogenic structures, can polymerize to producea complex variety of structures, including those previously mentionedfor the various respective functional groups.

Orientation of the Polymerized Product Containing Rodlike MesogenicStructures

During processing and/or curing of the alkenyl functional maleimidescontaining one or more rodlike mesogenic structures or the mixturescontaining said alkenyl functional maleimides, electric or magneticfields or drawing and/or shear stresses can be applied for the purposeof orienting the rodlike mesogenic moieties contained or developedtherein. As specific examples of these methods, Finkelmann, et. al.,Macromol. Chem., 180, 803-806 (March, 1979), which is incorporatedherein by reference, induced orientation in an electric field, ofthermotropic methacrylate copolymers containing mesogenic side chaingroups decoupled from the main chain via flexible spacers. Orientationin a magnetic field of mesogenic side chain groups decoupled from themain chain via flexible spacers has been demonstrated by Roth andKruecke, Macromol. Chem., 187, 2655-2662 (November, 1986), which isincorporated herein by reference. Magnetic field induced orientation ofmesogenic main chain containing polymers has been demonstrated by Moore,et. al., ACS Polymeric Material Sciences and Engineering, 52, 84-86(April-May, 1985), which is incorporated herein by reference. Magneticand electric field induced orientation of low molecular weight mesogeniccompounds is discussed by W. Krigbaum in Polymer Liquid Crystals, pages275-309 (1982), published by Academic Press, Inc., which is incorporatedherein by reference. The use of shear to induce orientation is alsodiscussed therein. When the curing is to be performed in an electric ormagnetic field, it is frequently of value to conduct simple preliminaryexperiments that allow for balancing of cure kinetics versus inductionof orientation under the particular experimental conditions beingemployed (i.e. catalyst(s) level being used, temperature used, inherentdielectric or diamagnetic susceptibility of the specific rodlikemesogenic structure(s) used, and the like). This is done recognizing therelatively greater ease of inducing orientation in low molecular weightmaterials versus polymeric materials containing mesogenic moieties.

In addition to orientation by electric or magnetic fields, the alkenylfunctional maleimides containing one or more rodlike mesogenicstructures or mixtures containing said alkenyl functional maleimides canbe oriented by drawing and/or shear forces which are induced by flowthrough dies, orifices and mold gates. A general discussion oforientation of thermotropic liquid crystalline polymers by this methodis given by S. K. Garg and S. Kenig in High Modulus Polymers, pages71-103 (1988) published by Marcel Dekker, Inc., which is incorporatedherein by reference. For the mesomorphic alkenyl functional maleimidesor mixtures containing said alkenyl functional maleimides, this drawingand/or shear orientation can conveniently be produced by or duringprocessing methods such as injection molding, extrusion, pultrusion,filament winding, filming and prepreging.

Other Components Which Can Be Employed

The alkenyl functional maleimides containing one or more rodlikemesogenic structures or mixtures containing said alkenyl functionalmaleimides can be blended with other materials such as solvents ordiluents, fillers including those comprising a liquid crystallinepolymer, pigments, dyes, flow modifiers, thickeners, reinforcing agents,mold release agents, wetting agents, stabilizers, fire retardant agents,surfactants, low profile additives, shrinkage control agents, otherresinous products, combinations thereof and the like.

These additives are added in functionally equivalent amounts, e.g., thepigments and/or dyes are added in quantities which will provide thecomposition with the desired color; however, they are suitably employedin amounts of from about zero to about 20, more suitably from about 0.5to about 5, most suitably from about 0.5 to about 3 percent by weightbased on the total weight of the composition.

Solvents or diluents which can be employed herein include, for example,hydrocarbons, ketones, aliphatic ethers, cyclic ethers, esters,chlorinated hydrocarbons, combinations thereof and the like.Particularly suitable solvents or diluents include, for example,toluene, xylenes, methylethyl ketone, methylisobutyl ketone, methylamylketone, chloroform, acetone, perchloroethylene, methylene chloride,tetrahydrofuran, 1,4-dioxane, ethyl acetate, butyl acetate, combinationsthereof and the like.

The modifiers such as thickeners, flow modifiers, shrinkage controlagents, low profile additives and the like can be suitably employed inamounts from about 0.05 to about 15, more suitably from about 0.1 toabout 10, most suitably from about 0.1 to about 5 percent by weightbased on the total weight of the composition.

Reinforcing materials which can be employed herein include natural andsynthetic fibers in the form of woven fabric, mats, monofilament,multifilament, unidirectional fibers, rovings, random fibers orfilaments, inorganic fillers or whiskers, hollow spheres, and the like.Suitable reinforcing materials include glass, ceramics, nylon, rayon,cotton, aramid, graphite, polyalkylene terephthlates, polyethylene,polypropylene, polyesters, carbon, boron, asbestos, combinations andhybrids thereof and the like.

Suitable fillers which can be employed herein include, for example,inorganic oxides, ceramic microspheres, plastic microspheres, glassmicrospheres, inorganic whiskers, calcium carbonate, graphite powder,sand, metal powders, combinations thereof and the like. The fillers canbe employed in amounts from about 0.1 to about 95, more suitably fromabout 5 to about 80, most suitably from about 10 to about 50 percent byweight of the total composition.

Uses for the Compositions

The compositions of the present invention can be employed in thepreparation of laminates, prepregs, composites, coatings, castings,pultruded products, filament wound products, films, molding and pottingformulations, injection molded products, and the like.

The following examples are illustrative of the invention but are not tobe construed as to limiting the scope thereof in any manner.

EXAMPLE 1 A. Synthesis of 4-Hydroxy-4"-nitrobenzanilide

p-Hydroxybenzoic acid (59.05 grams, 0.4275 mole), sodium ethoxidecatalyst (0.133 gram, 0.225% wt. of the p-hydroxybenzoic acid used) andN,N'-dimethylacetamide solvent (404 grams) are added to a reactorequipped with a reflux condenser and stirred under a nitrogen atmosphereat 80° C. p-Nitrophenylisocyanate (73.85 grams, 0.450 mole) is initiallyadded in an aliquot of 25.00 grams, followed by 25.00 and 23.85 gramaliquots eleven then nine minutes later, respectively, and so as tomaintain a 80° to 82° C. reaction temperature. After the last aliquot ofp-nitrophenylisocyanate is added, heating of the reactor commenced and a160° C. reaction temperature is achieved 24 minutes later. After threehours at the 160° C. reaction temperature, the reactor is cooled to 30°C. then the contents poured into one gallon of deionized water. Aprecipitated yellow powder is recovered via filtration of the aqueousslurry then dissolved into 1900 milliliters of boiling methanol andrefluxed therein (65° C.). After cooling the methanol solution to 5° C.and maintaining therein for twelve hours, a first crop of pale yellowcolored crystalline product is filtered off and dried at 110° C. undervacuum to a constant weight of 92.5 grams (79.6% isolated yield). Noattempt was made to recover a second crop of crystalline product fromthe mother liquor. Fourier transform infrared spectrophotometricanalysis of a nujol mull of a portion of the product on a sodiumchloride plate revealed the presence of the expected secondary amideN--H stretching (solid state) at 3385 cm⁻¹ (sharp), the secondary amidecarbonyl stretching (solid state) at 1655 cm⁻¹ (sharp), the hydroxylgroup O--H stretching centered at 3232 cm⁻¹ (broad) and the conjugatednitro group absorbances at 1537 and 1339 cm⁻¹ (sharp). Proton magneticresonance spectroscopy (250 MHz) further confirmed the product structureas 4-hydroxy-4'-nitrobenzanilide.

B. Synthesis of 4-Hydroxy-4'-aminobenzanilide

A portion (44.1 grams, 0.1708 mole) of 4-hydroxy-4'-nitrobenzanilidefrom A. above and ethanol (300 milliliters) are added to a 400milliliter heavy walled glass bottle then sparged with nitrogen. Afterremoval of air by nitrogen sparging, Raney nickel catalyst (5.5 grams ofa 75% wt. slurry in water at pH 10) is added to the slurry in the glassbottle which is then stoppered and multiply purged with hydrogen toreplace the nitrogen atmosphere. The bottle is then placed on a shakingtype agitator, and pressurized to 48 psig hydrogen. Shaking of thepressurized slurry at room temperature (25° C.) commences until 23.3hours later, the hydrogen pressure reading indicates that 47 psig ofhydrogen has been consumed. By the completion of the hydrogenation, thelight yellow colored reactant slurry became a light pink tan coloredproduct slurry. The product slurry is recovered, diluted intodimethylsulfoxide (300 milliliters) to provide a solution of productcontaining precipitated Raney nickel, then filtered through a mediumporosity fritted glass funnel. The recovered dimethylsulfoxide productsolution is rotary evaporated at 130° C. under vacuum to provide apowder product. The powder product is further dried at 120° C. undervacuum to a constant weight of 38.94 grams (99.88% isolated yield).Fourier transform infrared spectrophotometric analysis of a nujol mullof a portion of the product on a sodium chloride plate revealed thepresence of absorbances at 3376 (shoulder), 3351 (shoulder), 3316(sharp) and 3282 (shoulder) cm⁻¹ due to secondary amide group N--Hstretching (solid state), primary amine N--H group stretching andhydroxyl group O--H stretching; the secondary amide carbonyl stretching(solid state) at 1645 cm⁻¹ (sharp); and complete disappearance of theconjugated nitro group absorbances at 1537 and 1339 cm⁻¹ (sharp). Protonmagnetic resonance spectroscopy (250 MHz) further confirmed the productstructure as 4-hydroxy-4'-aminobenzanilide.

C. Synthesis of Monomaleimide of 4-Hydroxy-4'-aminobenzanilide

A portion (38.50 grams, 0.1687 mole) of 4-hydroxy-4'-aminobenzanilidefrom B. above and dry acetic acid (800 milliliters) are added to areactor and maintained under a nitrogen atmosphere with stirring. Thestirred slurry is maintained at 25° C. while maleic anhydride (16.54grams, 0.1687 mole) dissolved in dry acetic acid (100 milliliters) isadded to the reactor. One minute after the addition, a maximum exothermof 27° C. is achieved, then heating is started. Fifty nine minuteslater, the slurry reaches a reaction temperature of 110° C. and ismaintained therein for fourteen hours. The recovered product slurry isrotary evaporated at 80° C. under vacuum to provide a powder product.The powder product is then added to refluxing acetone (500 milliliters)and stirred therein as a slurry for five minutes. After cooling theacetone slurry to room temperature (25° C.), the first crop of lightyellow green colored product is filtered off and dried at 80° C. undervacuum to a constant weight of 43.87 grams (84.38% isolated yield). Noattempt was made to recover a second crop of product the mother liquor.Fourier transform infrared spectrophotometric analysis of a nujol mullof a portion of the product on a sodium chloride plate revealed thepresence of absorbances at 3349 (sharp), 3289 (sharp) and 3087 (broad)cm⁻¹ due to secondary amide group N--H stretching (solid state),hydroxyl group O--H stretching; the secondary amide carbonyl stretching(solid state) at 1649 cm⁻¹ (sharp); and the maleimide carbonyl groupstretching at 1702 cm⁻¹ (sharp). Proton magnetic resonance spectroscopy(250 MHz) further confirmed the product structure as the maleimide of4-hydroxy-4'-aminobenzanilide.

D. Synthesis of Allylated 4-Hydroxy-4'-aminobenzanilide Maleimide

A portion (0.45 gram, 1.46 mmole) of the maleimide of4-hydroxy-4'-aminobenzanilide from C. above, allyl chloride (2.82 grams,36.8 mmole), 97+% sodium hydroxide powder (0.18 gram, 4.5 mmole),tetrabutylammonium bromide catalyst (0.014 gram, 3% weight of4-hydroxy-4'-aminobenzanilide maleimide used) and dimethylsulfoxidesolvent (4.0 grams) are added to a reactor and maintained under anitrogen atmosphere with stirring and heating to 40° C. After six hoursat the 40° C. reaction temperature, the product is diluted with toluene(25 milliliters), then added to a separatory funnel. The product isextracted with two 10 milliliter portions of deionized water then driedover anhydrous sodium sulfate. The dry toluene extract is filtered andsolvent removed by rotary evaporation under a vacuum at 80° C. toprovide 0.27 grams (product lost on glassware not accounted for) of alight amber colored tacky liquid. Fourier transform infraredspectrophotometric analysis of a neat film of a portion of the producton a sodium chloride plate revealed the presence of the expectedsecondary amide group N--H stretching (solid state) at 3316 cm⁻¹, thesecondary amide group carbonyl stretching (solid state) at 1643 cm⁻¹(sharp), and the maleimide group carbonyl stretching 1722 cm⁻¹ (sharp),as well as disappearance of the portion of the multiple absorbancesattributed to hydroxyl group O--H stretching. Proton magnetic resonancespectroscopy (250 MHz) further confirmed the product structure.

E. Characterization of Allylated 4-Hydroxy-4'-aminobenzanilide Maleimidefor Liquid Crystallinity

A portion (9.09 milligrams) of allylated 4-hydroxy-4'-aminobenzanilidemaleimide from D. above is analyzed by differential scanning calorimetryusing a heating rate of 10° C. per minute under a stream of nitrogenflowing at 35 cubic centimeters per minute and the indicated temperatureranges. The following results were obtained:

    ______________________________________                                                 OBSERVED                                                                      TRANSITION                                                           CYCLE    TEMPERATURES  EN-                                                    DESIGNA- (°C.)  THALPY                                                 TION     midpoint/range                                                                              (j/g)     COMMENTS                                     ______________________________________                                        First    283/204-313   556.7     Single peak                                  heating                          exotherm                                     (30 to                                                                        425° C.)                                                               ______________________________________                                    

The cured product is recovered from the differential scanningcalorimetry as a rigid black solid. When crushed to a powder on a glassmicroscope slide then observed via crosspolarized light microscopy at35× magnification, a high degree of birefringence was observed in thethermoset product.

Analysis of the allylated maleimide via crosspolarized light microscopyis completed using a microscope equipped with a programmable hot stageusing a heating rate of 10° C. per minute and 35× magnification. Thefollowing results are obtained:

    ______________________________________                                                    OBSERVED                                                                      TRANSITION                                                        CYCLE       TEMPERATURES                                                      DESIGNATION (°C.)  COMMENTS                                            ______________________________________                                        First        25           Viscous liquid                                      heating     170           Thin isotropic fluid                                            279           Viscosity increasing                                            284           Cures to a non-                                                               birefringent solid                                  ______________________________________                                    

When the cured solid was scratched with a steel needle, it produced abirefringent streak in the direction of the scratch.

EXAMPLE 2 A. Synthesis of α-p-Nitrophenyl-p-acetoxycinnamic Acid

p-Nitrophenylacetic acid (94.02 grams, 0.519 mole) and 1.038N sodiumhydroxide solution (500 mL) are added to a 1,000 mL beaker and heatedwith stirring to 60° C. The resultant solution is rotary evaporatedunder vacuum until final conditions of 110° C. and 1 mm Hg are achievedand maintained for 30 minutes. A portion (101.6 grams, 0.50 mole) of theresultant dry white carboxylic acid sodium salt, p-hydroxybenzaldehyde(61.06 grams, 0.50 mole) and acetic anhydride (250 grams) are added to areactor equipped with a reflux condenser and stirred under a nitrogenatmosphere at a 147° C. Refluxing continued over the next twenty hoursat which time the temperature has increased to 159° C. At this time, thereactor is cooled to 100° C. and ethanol (300 mL) and water (50 mL) areadded. The resultant slurry is boiled at 89° C. for one hour followed bycooling to 50° C. and filtration. The filtrate is added to deionizedwater (1500 mL) and the resultant precipitate recovered by filtration.The precipitate is exhaustively extracted with deionized water saturatedwith sodium carbonate. The combined extracts are filtered thenneutralized with concentrated hydrochloric acid inducing formation of aprecipitate. The precipitate is recovered by filtration then dried at50° C. in a forced air convection type oven. The dry powder is added toa beaker along with carbon tetrachloride (200 mL) then stirred withheating to a boil. Acetic acid (40 mL) is added to the boiling slurrythen heating back to a boil resumed. After boiling is achieved, theslurry is maintained at 4° C. for 15 hours. The precipitate is recoveredby filtration and dried at 70° C. under a vacuum of 5 mm Hg to aconstant weight of 38.55 grams of brilliant light yellow coloredcrystalline powder.

B. Synthesis of 4-Nitro-4'-hydroxystilbene

A portion (36.75 grams) of α-p-nitrophenyl-p-acetoxycinnamic acid fromA. above, ethanol (300 mL) and concentrated hydrochloric acid (300 mL)are added to a reactor equipped with a reflux condenser and stirredunder a nitrogen atmosphere. Heating commenced and a reflux is achievedat 93° C. Refluxing continued over the next 262 minutes at which timethe temperature has increased to 95° C. At this time, the contents ofthe reactor are poured into deionized water (one liter) and theresultant precipitate recovered by filtration. The wet filter cake iswashed with two portions (500 mL) of deionized water then dissolved instirred ethanol (750 mL) maintained at 82° C. The resultant solution ismaintained at 4° C. for 15 hours. The precipitate is recovered byfiltration and dried at 75° C. under a vacuum of 2 mm Hg to a constantweight of 22.70 grams of light orange colored crystalline needles.Fourier transform infrared spectrophotometric analysis of a potassiumchloride pellet of a portion of the product revealed the presence of theexpected hydroxyl group O--H stretching centered at 3422 cm⁻¹ (broad),conjugated nitro group absorbances at 1516 and 1337 (1317 shoulder) cm⁻¹(sharp) and the ethylene C--H out-of-plane deformation at 972 cm⁻¹.

C. Synthesis of 4-Hydroxy-4'-aminostilbene

A portion (20.9 grams, 0.0866 mole) of 4-nitro-4'-hydroxystilbene fromB. above and ethanol (300 mL) are added to a 400 milliliter heavy walledglass bottle then sparged with nitrogen. After removal of air bynitrogen sparging, Raney nickel catalyst (2.5 grams of a 50% wt. slurryin water at pH 10) is washed one time with ethanol, then added to theslurry in the glass bottle which is then stoppered and multiply purgedwith hydrogen to replace the nitrogen atmosphere. The bottle is thenplaced on a shaking type agitator, and pressurized to 46.5 psig (320.6kPa) hydrogen. Shaking of the pressurized slurry at room temperature(25° C.) commences until 28.5 hours later, the hydrogen pressure readingindicates that 19.6 psig (135.1 kPa) of hydrogen has been consumed. Theproduct slurry is recovered, diluted into dimethylsulfoxide (150 grams)to provide a solution of product containing precipitated Raney nickel,then filtered through a medium porosity fritted glass funnel. Therecovered dimethylsulfoxide product solution is rotary evaporated at130° C. under vacuum to provide a powder product. The power product isfurther dried at 100° C. under vacuum of 2 mm Hg to a constant weight of18.17 grams (99.25% isolated yield ) of orange brown colored powder.Fourier transform infrared spectrophotometric analysis of a potassiumchloride pellet of a portion of the product revealed the presence ofabsorbances at 3363 (sharp) and 3289 cm⁻¹ (sharp) due to primary amineN--H group stretching and hydroxyl group O--H stretching, completedisappearance of the conjugated nitro group absorbances at 1516 and 1337(1317 shoulder) cm⁻¹ (sharp) and the ethylene C--H out-of-planedeformation at 965 cm⁻¹. Nuclear magnetic resonance spectroscopyconfirmed the integrity of the stilbene ethylenic unsaturated structure.

D. Synthesis of Monomaleimide of 4-Hydroxy-4'-aminostilbene

A portion (17.63 grams, 0.0835 mole) of 4-hydroxy-4'-aminostilbene fromC. above, dry acetic acid (500 mL) and maleic anhydride (8.18 grams,0.0835 mole) dissolved in acetic acid (100 grams) are added to a reactorand maintained under a nitrogen atmosphere with stirring. Heatingcommenced and the slurry reaches a reaction temperature of 110° C. andis maintained thereat for fourteen hours. The recovered product slurryis rotary evaporated at 70° C. under vacuum of 1 mm Hg to provide apowder product. The powder product is then added to refluxing acetone(75 mL) and stirred therein as a slurry for five minutes. After coolingthe acetone slurry to room temperature (24° C.), the first crop ofgolden yellow colored product is filtered off and is dried at 70° C.under vacuum to a constant weight of 19.14 grams (78.73% isolatedyield). No attempt is made to recover a second crop of product from themother liquor. Fourier transform infrared spectrophotometric analysis ofa potassium chloride pellet of a portion of the product revealed thepresence of absorbances centered at 3442 cm⁻¹ (broad) due to thehydroxyl group O--H stretching, the maleimide carbonyl group stretchingat 1702 cm⁻¹ (sharp) (1775 cm⁻¹ shoulder) and the ethylene C--Hout-of-plane deformation at 965 cm³¹ 1. Differential scanningcalorimetry of a portion (10.95 milligrams) of the product using aheating rate of 10° C. per minute under a stream of nitrogen flowing at35 cubic centimeters per minute and a temperature range of 30° to 375°C. revealed a single exotherm with an onset temperature of 196° C.,midpoint temperature of 254° C., endpoint temperature of 369° C. and anenthalpy of 218 j/g.

E. Synthesis of Allylated of 4-Hydroxy-4'-aminostilbene Maleimide

A portion (1.45 grams, 4.98 mmole) of the maleimide of4-hydroxy-4'-aminostilbene from D. above, allyl chloride (9.39 grams,0.123 mole), 97+% sodium hydroxide powder (0.60 gram, 15.0 mmole),tetrabutylammonium bromide catalyst (0.044 gram, 3% weight of4-hydroxy-4'-aminostilbene used), and dimethylsulfoxide solvent (12.0grams) are added to a reactor and maintained under a nitrogen atmospherewith stirring and heating to 40° C. After six hours at the 40° C.temperature, the product is diluted with toluene (60 milliliters), thenadded to a separatory funnel. The product is extracted with two 20milliliter portions of deionized water then dried over anhydrous sodiumsulfate. The dry toluene extract is filtered and solvent removed byrotary evaporation under a vacuum at 80° C. to provide 1.53 grams of anamber colored solid. Fourier transform infrared spectrophotometricanalysis of a neat film of a portion of the product on a sodium chlorideplate revealed the presence of the expected maleimide group carbonylstretching absorbance at 1709 cm⁻¹ (sharp) (1762 cm⁻¹ shoulder) and theethylene C--H out-of-plane deformation at 965 cm⁻¹, as well as completedisappearance of the hydroxyl group O--H stretching absorbance. Protonmagnetic resonance spectroscopy (250 MHz) further confirmed the productstructure.

F. Characterization of Allylated of 4-Hydroxy-4'-aminostilbene Maleimidefor Liquid Crystallinity

A portion (10.13 milligrams) of the allylated of4-hydroxy-4'-aminostilbene maleimide from E. above is analyzed bydifferential scanning calorimetry using a heating rate of 10° C. perminute under a stream of nitrogen flowing at 35 cubic centimeters perminute and the indicated temperature ranges. The following results areobtained:

    ______________________________________                                                   Observed                                                                      Transition                                                                    Temperatures                                                       Cycle      (°C.)                                                                              Enthalpy                                               Designation                                                                              midpoint/range                                                                            (j/g)      Comments                                    ______________________________________                                        First      68/42-84    14.4       Endotherm                                   Heating    261 and 336 351.9      Pair of                                     (30 to     195-404                exotherms                                   425° C.)                   which                                                                         merge                                       ______________________________________                                    

The cured product is recovered from the differential scanningcalorimetry as a rigid black solid. When crushed to powder on a glassmicroscope slide then observed via crosspolarized light microscopy at35× magnification, a high degree of birefringence was observed in thethermoset product.

Analysis of the alkylated maleimide via crosspolarized light microscopyis completed using a microscope equipped with programmable hot stageusing a heating rate of 10° C. per minute and 35× magnification. Thefollowing results are obtained:

    ______________________________________                                                  Observed                                                                      Transition                                                                    Temperatures                                                                  (°C.)                                                        Cycle     midpoint/                                                           Designation                                                                             range        Comments                                               ______________________________________                                        First      25          Birefringent solid                                     Heating    56          Flows as birefringent fluid                                                   when compressed between                                                       slide and coverslip. Gives                                                    opalescence as stirred                                            64          Thin birefringent fluid                                          165          Birefringent fluid                                               207          Birefringence decreasing                                         217          Fluid shows birefringence                                                     when sheared                                                     222          Isotropic fluid                                                  259          Viscosity increases                                              275          Cures to a non-birefringent                                                   solid                                                  ______________________________________                                    

When the cured solid was scratched with a steel needle it produced abirefringent streak in the direction of the scratch. Crushing the curedsolid produced a highly birefringent powder.

EXAMPLE 3 A. Homopolymerization of Allylated 4-Hydroxy-4'-aminostilbeneMaleimide Below Claisen Rearrangement Temperature

A portion (0.20 gram) of the allylated 4-hydroxy-4'-aminostilbenemaleimide from Example 2-E is dissolved in toluene (5 milliliters),heated to 100° C. with mixing, then filtered while hot. The resultantsolution is contained in a glass vial, sparged with nitrogen, then asingle drop of boron trifluoride etherate is added. After sealing thevial under a nitrogen atmosphere, heating to 100° C. commences. Afterthe vial cools to room temperature (24° C.), a polymer precipitate isfiltered off, washed with deionized water (5 milliliters), then dried at60° C. under a vacuum of 2 mm Hg.

B. Characterization of Homopolymer of Allylated4-Hydroxy-4'-aminostilbene Maleimide for Liquid Crystallinity

Analysis of the homopolymer from A above via crosspolarized lightmicroscopy is completed using a microscope equipped with a programmablehot stage using a heating rate of 10° C. per minute and 35×magnification. The following results are obtained:

    ______________________________________                                                  Observed                                                                      Transition                                                          Cycle     Temperatures                                                        Designation                                                                             (°C.) Comments                                               ______________________________________                                        First      25          Birefringent solid                                     Heating   185          Birefringent solid with                                                       softening observed as                                                         compressed                                                       193          Highly birefringent; flows                                                    as compressed                                                    300          Birefringent viscous fluid                             ______________________________________                                    

What is claimed is:
 1. A product resulting from curing a compoundcontaining at least one alkenyl group, at least one maleimide group andat least one rodlike mesogenic moiety, optionally in the presence of oneor more catalysts.
 2. A product of claim 1 wherein the compound beingcured is represented by the following Formulas I, II, III or IV##STR32## wherein at least about 80 percent of the --A-- linkages inFormulas I, II and IV and the direct bond in Formula III and the Ygroups are in the para position with respect to each other; one Y groupis an alkenyloxy group represented by the formulas --O---CR¹ ═CHR¹,--O--CHR¹ --CR¹ ═CHR¹, ##STR33## and the other Y group is a maleimidegroup represented by the formula ##STR34## each A is independently --CR¹═CR¹ --, --C.tbd.C--, --N═N--, --CR¹ ═N--, --O--CO--, --NR¹ --CO--,--CR¹ ═N--N═CR¹ --, --CR¹ ═CR¹ --CO--, --CO--O--, --CO--NR¹ --,--CO--CR¹ ═CR¹ --, --CR¹ ═CR¹ --O--CO--(CH₂)_(n') --, --N═CR¹ --,--(CH₂)_(n') --CO--O--CR¹ ═CR¹ --, --CR¹ ═CR¹ --O--CO--, --CO--O--CR¹═CR¹ --, --CO--O--N═CR¹ --, --CR¹ ═N--O--CO--, --CR¹ ═CR¹ --CO--O--,--CO--S--, --O--CO--CR¹ ═CR¹ --, --CR¹ ═CR¹ --CO--O--(CH₂)_(n') --,--S--CO--, --(CH₂)_(n') --O--CO--CR¹ ═CR¹ --, --CHR¹ --CHR¹ --CO--O--,--O--CO--CHR¹ --CHR¹ --CHR¹ --, --C.tbd.C--C.tbd.C--, --CR¹ ═CR¹ --CR¹═CR¹ --, --CO--NR¹ --NR¹ --CO--, ##STR35## each A' is independently adivalent hydrocarbyl group having from 1 to about 10 carbon atoms; eachA" is independently an alkylene group having from 1 to about 10 carbonatoms carbon atoms, a direct bond, --O--, --CO--, --S--, --S--S--,--SO--, --SO₂ -- or --O--CO--O--; each A¹ is independently a --CO--,--O--CO--, --CO--O--, --CO--NR¹ --, or --NR¹ --CO-- group; each R isindependently hydrogen or a hydrocarbyl or hydrocarbyloxy group havingfrom 1 to about 10 carbon atoms, a halogen atom, a nitro group, anitrile group, a phenyl group or a --CO--R¹ group; each R¹ isindependently hydrogen or a hydrocarbyl group having 1 to about 3 carbonatoms; n has a value of zero or one, n' has an average value from zeroto about 6; and p has an average value from 1 to about 30; with theproviso that any of the aromatic rings can, if desired, contain anitrogen, oxygen or sulfur heteroatom.
 3. A product of claim 2 whereineach A' independently has from 1 to about 4 carbon atoms; when A" is analkylene group, it has from 1 to about 4 carbon atoms; each R isindependently hydrogen or a hydrocarbyl group having from 1 to about 4carbon atoms, chlorine or bromine; n' has an average value from zero toabout
 3. 4. A product of claim 1 wherein the compound that is cured isselected from the group consisting of ##STR36## ##STR37## where V¹ is amaleimide group represented by the formula ##STR38## and V is analkenyloxy group, represented by the formulas --O--CR¹ ═CHR¹, --O--CHR¹--CR¹ ═CHR¹, ##STR39## and where R¹ is independently hydrogen or ahydrocarbyl group having 1 to about 3 carbon atoms.
 5. The product ofclaim 1, 2, 3, or 4 wherein the compound or compounds containing therodlike mesogenic moieties are oriented prior to curing or during curingor both prior to and during curing.
 6. The product of claim 5 whereinsaid orientation is accomplished by use of an electric or magnetic fieldor by drawing or shear forces or any combination thereof.